Switch unit



June 3, 1941. w. H. FRANK EIAL SWITCH UNIT Filed Sept. 6, 1938 3 Sheets-Sheet 1 1NVENTOR I )4 7 f z: g BY 00 ATTORNEY.

June 3, 1941. w. H. FRANK IE! AL SWITCH UNIT Filed Sept. 6, 1938 3 Sheets-Sheet 2 I INVENT OR J ATTORNEY June 3, 1941. w. H. FRANK ETAL 2,244,359

SWITCH UNIT Filed Sept. 6, 1938 3 Sheets-Sheet 3 NVENTORS BY JZJW ORNEY.

Patented June 3, 1941 SWITCH UNIT William H. Frank and Joseph A. Messing, Detroit, Mich.

Application September 8, 1938, Serial No. 228,584

5 Claims.

This application relates to switch units and more particularly to switch units comprising in- I sulation blocks in cavities of which are disposed switches.

One object of the invention is to provide n a switch unit of such character an arrangement employing a rocker type actuating handle for the movable contact, with the handle being formed to form and provide a complete closure for the front of the cavity at all times and in all positions of the handle, thereby eliminating the masking plate sometimes provided on switch units; as for example the switching unit disclosed in the patent to William H. Frank, No. 2,086,796 of July 13, 1937.

A further object is to provide in a switching unit of such character a handle arrangement employing one or more rocker type handles journailed on a cross bar passing through the handles and having its ends stationarily mounted on the switching unit, with the handles disposed in and closing cavities of th unit.

A still further object is a novel switching arrangement wherein movement of the handle in either direction causes a positive kick to the switching parts by rocking them or tilting them on wall parts. of the cavities containing the switching parts, such rocking action starting or kicking the switch parts in their movement and at the same time stressing the springs of the switching parts so that these springs will relieve themselves of their stresses at later stages of the movements for snap action.

A still further object is a novel arrangement of switching parts permitting simplified assembly of the switching parts with respect to one another and with respect to the switching unit as a whole.

Still further objects are novel contact arrangements, these having novel formations of arcing tips and also novel wedging formations.

For an understanding of the embodiment herein disclosed, reference should be had .to the appended drawings. In these drawings,

Fig. 1 is a front view of a panelboard unit;

Fig. 2 is a side view of the same;

Fig. 3 is a cutaway view showing the switch parts in'"on position;

Figs. 4 and 5 are similar views showing the parts in "off" position. and at the start of movement towards the "off" position, respectively;

Fig. 6 is a partial back view of the unit;

Figs. 7 to 13 show switch parts per se.

Referring to the drawings, it will be seen that these show a unit in the form of a hollow block of insulation, such as porcelain, having in its back channels it in which are adapted to be disposed bus bars ii to which are connected by means of connection screws i2 line contacts I which in turn are connected by means of the switch parts hereafter to be described to load contacts I! connectedby fuses, such as the plug fuses i8 shown at one end of the unit or the cartridg fuses i1 shown at the other end of the unit, to load conductor terminal binding posts, such as those shown at ii.

The switches themselves comprise rocker type handles 20 having slots 2i through which pass pivot bars 22 whose ends are seated in seats formed in th block or unit, the bars 22 thus loosely pivoting the handles 20 so that these move individually on the bars 22.

Formed on each handle is a lug 23 having a hole 24 receiving extrusions 25 of the U-shaped part 26 of a two part spring link 21. The lower end of the latter passes through a hole formed in the bight of a U-shaped movable contact 2' and against this bight and also against the U- shaped part 26 of the spring link 21 reacts a coiled compression spring 28. A washer l0 surrounds the parts of the link 21 and holds them together.

The movable contact 2| has at its free end outwardly directed lugs 3i forming knife edge bearings therefor, these seating in V-shaped notches 32 formed in shoulder surfaces on the interior of the cavity of the block which receives the switching parts.

The movable contact is formed with projecting contact tips I! which are formed to engage and make contact with the tips 34 of the stationary contacts i4 and i5.

At each end of the block there will be two interconnected contacts I4, connected to a bus bar, and, outside of these, two load contacts I! connected to the load conductors. Ther will be two movable contacts 28 and each will serve to make with and connect one of the line contacts it with one of the load contacts II.

The parts 33 and 34 of the contacts are extended, as shown at 35, to provide arcing tips.

'These are not engaged when the switch is in the on position, Fig. 3, but are engaged during movement of the switch to andfrom on" position; the arcing tips 35 will mutually engage first to establish contact and thereafter the movable arcing tips will pass beyond the stationary arcing tips and the various arcing tips will seat themselves in the notches It of the engaged contacts, and the arcing tips will thus be out of engagement so that any pitting on the arcing tips will not impair the final contact. In movement from on position, the unengaged arcing tips of the movable contact will move out of the notches 36 1 of the stationary contacts and into engagement with the arcing tips of the stationary contacts and thereafter will leave such stationary contact arcing tips, to break the circuit.

Each stationary contact has a portion 31 extruded or pushed out at an angle, as shown in Fig. 11. The final contact of the switch in its on" position is between portions 33 of the movable contact and these extrusions 31. .As these extrusions are at an angle to the main contacts a wedging action is secured when the movable contact wedges itself into engagement with the stationary contacts for good contact. Further, the final contact is made on these inclined extrusions 31 and the portions 33 of the movable contact, which are different portions of both the movable and stationary contacts, than the arcing tips 35.

It will be observed that when a handle is rocked on its pivot bar 22 the spring 29 connected to the handle will teeter on the ends X and XX formed on the barriers of insulation adjacent the switch parts. In movement from on to off, the spring 29 will teeter on the ends X, as shown in Fig. 3, and in reverse movement the spring will teeter on the ends XX, Fig. 3. In this way the spring will function as part of the spring link to provide a positive actuation for the switch parts at the beginning of their movement.

The engagement of the spring with the surfaces X and XX positively forces the movable contact in its respective direction. During this positive movement the spring is being tensioned so that after the over-center position is reached, the movable contact moves under the influence of the spring for a snap action. The movable and stationary contacts are so proportioned that the positive action does not break the circuit completely, the final break of the contact being under the influence of the spring for snap action. Similarly, when the switch is thrown from the on to the off positions, the positive action does not cause the contacts to engage, but the contacts are thrown into engagement by the influence of the springs for snap action.

It will also be observed that each rocker type handle may be provided on its exposed or handle surface with an undercut notch 40 for receiving a circuit indicating card, as for example the card shown at 4| in Fig. 1.

An important feature of the unit hereof is the manner of assembly.

A handle 20, a spring link 21, a movable contact 38, a spring 29, and a washer 30 are assembled into a sub-assembly as follows: The two parts of the spring link are placed together and their part 26 is fitted around the lug 23 of the handle so that extrusions 25 of the part 26 will dispose themselves in a handle hole 24, whereupon the washer 30 is slipped over the free ends of the spring link. Then the spring is also slipped over the spring link to abut the washer 30 and the movable contact is also slipped over the free ends of the spring link. Thereupon these free ends are bent from the dotted line position of Fig. 12 to the full line position of that figure to complete the sub-assembly of the switch.

A bar 22 is then threaded through two switch handle holes 2| and the pair of switches with their bar are dropped into the cavity of the in- I sulation block, lugs 3| of the switches seating themselves in the V-shaped notches 32 on the shoulders or ledges of the interior of the cavity. Tightening of the screw 42 passing through the hol 43 of the bar 22 will complete the assembly and at the same time pull U-shaped contacts 28 slightly away from the bent over ends oi the spring link 21 to tension the spring 29 slightly for quick make and break.

We claim:

1. A switch unit comprising a block of insulation having a cavity therein formed with an enlarged shoulder portion at its upper end, a U shaped movable contact within the cavity, a link within the movable contact having one end connected to the bight thereof, and having its other end free and enlarged, a coiled compression spring surrounding the link and having one end bearing against the bight of the movable contact and its other end bearing against the enlarged portion of the link, and a handle pivotally connected to the free end of the link, near the enlarged portion thereof, the handle having a transverse hole, an axle for the handle bearing on the block and passing through said hole, the handle being within the enlarged upper portion of the cavity and being formed to form a complete closure for the cavity at all times and in all positions of the handle, the movable contact having at its free ends laterally extending portions bearing on the upper surfaces of the exposed shoulders of the enlarged portion of the cavity to form trunnions for the movable contact, link arid spring, the construction being such that the movable contact, link and spring may be relatively assembled to form a sub unit which can be assembled with the block by being dropped into the cavity thereof, so that the movable contact trunnions rest on the cavity shoulders.

2. A switch unit comprising a block of insulation having a cavity therein formed with an enlarged shoulder portion at its upper end, a U shaped movable contact within the cavity, a link within the movable contact having one end connected to the bight thereof, and having its other end free and enlarged, a coiled compression spring surrounding the link and having one end bearing against the bight of the movable contact and its other end bearing against the enlarged portion of the link, and a handle pivottally connected to the free end of the link, near the enlarged portion thereof, the handle having a transverse hole, an axle for the handle bearing on the block and passing through said hole, the handle being within the enlarged upper portion of the cavity and being formed to form a complete closure for the cavity at all times and in all positions of the handle, the movable contact having at its free ends laterally extending portions bearing on the upper surfaces of the exposed shoulders of the enlarged portion of the cavity to form trunnions for the movable contact, link and spring, the construction being such that the movable contact, link and spring may be relatively assembled to form-a sub unit which can be assembled with the block by being dropped into the cavity thereof, so that the movable contact trunnions rest on the cavity shoulders, the transverse hole of the handle being in the form of a slot, with large ends and a small center portion, and the axle being a stationary strap or bar of a thickness approximating the width of the small center portion of the handle slot, such small center portion hearing at all times on the bar, and the enlarged ends of the slot providing limited travel of the handle around the strap.

3. A switch unit comprising a block of insulation having a cavity therein formed with an en-' larged shoulder portion at its upper end, a U shaped movable contact within the cavity, a link within the movablecontact having one end connected to the bight thereof, and having its other end free and enlarged, a coiled compression spring surrounding the link and having one end bearing against the blight of the movable contact and its other end bearing against the enlarged portion of the link, and a handle pivotally connected to the free end of the link, near .the enlarged portion thereof, the handle having a transverse hole, an axle for the handle bearing on the block and pasing through said hole, the handle being within the enlarged upper portion of the cavity and being formed to form a complete closure for the cavity at all times and in all positions of the handle, the movable contact having at its free ends laterally extending portions bearing on the upper surfaces of the exposed shoulders of the enlarged portion of the cavity to form trunnions for the movable contact, link and spring, the construction being such that the movable contact, link and spring may be relatively assembled to form a sub unit which can be assembled with the block by being dropped into the cavity thereof. so that the movable contact trunnions' rest on the cavity shoulders, the transvereeholeofthehandlebeingintheform of a slot, with t curb and a small center portion, and the axle being a stationary strap or bar of a thickness approximating the width of the small center portion of the handle slot, such small center portion hearing at all times on the bar. and the enlarged ends of the slot providing limited travel of the handle around the strap, the handle and block being so formed relatively that the handle ends are normally accessible only for push to rock the handle around the axle.

4. A switch unit. comprising a block of insulation having a cavity therein formed with an enlarged shoulder portion at its upper end, a U

handle being within the enlarged upper portion of the cavity and being formed to form a complete closure for the cavity at all times and in all positions of the handle, the movable contact having at its free ends laterally extending portions bearing on the upper suriaces of the exposed shoulders of the enlarged portion of the cavity to form trunnions tor the movable contact, link and spring. the construction being such that the mov-' able contact, link and spring may be relatively assembled to form a sub unit whlch can be assembled with the block by being dropped into the cavity thereof, so that the movable contact trunnions rest on the cavity shoulders, the handle and block being so formed relatively that the handle ends arenormally accessible only for push to rock the handle around the axle.

5. 'A switch unit comprising a block of inside-- tion having a cavity therein formed with an enlarged shoulder portion at its upper end, a'U shaped movable contact within the cavity, a link within the movable contact having one end connected to the bight thereof, and having its other end free and enlarged. a coiled comprasion springsurroimdingthelinkandhavingone end bearing against the bight of the movable contact and its other end bearing against the enlarged portion of the link, and a handle pivotally connected to the free end of the link, near the enlarged portion thereof, the handle having a transverse hole, an axle for the handle bearing on the block and passing through said hole, the handle being within the enlarged upperportion of the cavity and being formed to form a complete closure for the cavity at all times and in all positions of the handle, the movable contact having at its free ends laterally extending porionsbearlngontheuppersurfaceofthe exposed shoulders of the enlarged portion of the cavity to form trunnions for the movable contact, link and spring, the construction being such that the movable contact. link and spring may be relatively assembled to form a sub \mit which can be assembled with the block by being dropped into the cavity thereof, so that the movable contact trunnicm rest on the-cavity shoulders, the han die on block being so formed relatively that the handle ends are normally accessible only for push to rock the handle around the axle, the transverse hole of the handle being in the form of a slot, with large ends and a small center portion, and the axle being a stationary strap or bar of a thickness approximating the width of the small center portion of the handle slot, such small center portion hearing at all times on the bar, and the enlarged ends of the slot providing limited travel of the handle around the strap, the handle being assembled with the movable contact, link, and spring into said sub unit, with the axle strap being within the handle prior to the completion of the assembly.

WILLIAM H. FRANK. JOSEPH A. MESSING. 

